I can't speak for all the GO owners, but our test modded 7 port whent 9 gallons, it still runs on all original parts, has just lost what it once was, but i have heard between 6 and 9 gallons from guys that race them pretty hard, this was the numberone thing that turned me on to GO motors, and the price is unbeatable, P/S/R sets are about 90 to 100, depending where you get them.